Treatment planning for scanned ion beams

Since 1997 a radiotherapy unit using fast carbon ions is operational at GSI. An intensity-controlled magnetic raster scanner together with a synchrotron allowing fast energy variation enable a unique method of purely active dose shaping in three dimensions. This contribution describes the necessary steps to establish a treatment planning system for this novel modality. We discuss the requirements for the physical beam model and the radiobiological model. Based on these we chose to implement a home-grown pencil beam model to describe the ion-tissue interaction and the Local Effect Model to calculate the RBE voxel-by-voxel. Given the large number of degrees of freedom biological dose optimization must be achieved by means of inverse treatment planning. All ion-related aspects are collected in our TRiP98 software. Biological dosimetry measuring cell survival in two dimensions turns out to be a good way to verify the model predictions as well as the actual irradiation procedure. We show a patient example and outline the future steps towards a dedicated clinic facility for all light ions.

Spondylodiscitis as the first manifestation of Whipple?s disease ?a removal worker with chronic low back pain

Whipple's disease is a rare systemic infectious disease caused by the actinobacterium Tropheryma whipplei. Spondylodiscitis is an extremely rare manifestation of the infection and has previously been described in only three case reports. We present a 55-year-old man with persistent lumbago and signs of systemic illness, but without any gastrointestinal symptoms or arthralgia. The signal response in the lumbar spine in magnetic resonance tomography, both native and after intravenous gadolinium administration, was compatible with spondylodiscitis at the L4/L5 level. Culture of a specimen obtained by radiographically guided disc puncture and repeated blood cultures remained sterile. Tropheryma whipplei was detected by PCR amplification in material obtained from the disc specimen, from a biopsy of the terminal ileum and from the stool. The histology of duodenum, terminal ileum, colon and disc material was normal and, in particular, showed no PAS-positive inclusions in macrophages. Long-term antibiotic treatment with sulphamethoxazole and trimethoprim was successful, with marked improvement of the low back pain and normalisation of the systemic inflammatory signs. The possibility of Whipple's disease must be suspected in the case of a 'culture-negative' spondylodiscitis even if there are no gastrointestinal symptoms and no arthralgia present.

Comparison of three distraction methods and conventional radiography for early diagnosis of canine hip dysplasia

Two radiographic distraction techniques (one employing a wooden lath and, the other, a PennHip distractor), an ultrasonographic distraction method and conventional radiographic Fédération Cynologique Internationale (FCI) hip score were evaluated in eight-month-old Labrador retrievers to determine the most reliable method for predicting radiographic FCI hip score at the age of one year. With reference to the FCI hip score, sensitivity and specificity of the PennHip method were 100 per cent and 54 per cent; sensitivity and specificity of the lath technique were 85 per cent and 71 per cent; whereas they were 62 per cent and 67 per cent for the ultrasonographic method. For all distraction methods, the positive predictive value (PPV) was moderate and the negative predictive value (NPV) was high. Sensitivity, specificity, PPV and NPV were 100 per cent for the FCI hip score. It is concluded that, at the age of eight months, FCI hip score is the most reliable method for predicting FCI hip score at the age of one year in the colony of dogs investigated. Both the PennHip and lath method were also clinically reliable techniques in predicting true negatives. The ultrasonographic distraction method was moderately reliable.

[Rehabilitation after injuries to the metacarpal and finger joints]

Finger joint injuries are the most frequent injuries of the hand. Besides operative and conservative therapy of these injuries, it is even more important to ensure a correct and thorough follow-up treatment. The aim of good rehabilitation is a painless, stabilized joint. Based on the therapeutic guidelines of the department of orthopedics, traumatology, and hand surgery of the Free University Berlin, the rehabilitation of these injuries is discussed.

[Rehabilitation after replantation]

Limb replantation represents a particular surgical challenge. Rehabilitation and functional integration of the patient into everyday life has proven to be as equally important as the operation itself. This requires intensive and long-term cooperation between surgeon, therapist, and patient since replanted limbs without restoration of function are of no use. Besides physiotherapy, ergotherapy is highly important for this since it helps to reactivate daily activities.Also, tactile gnosis and protecting nervous sensibility and motor function can be improved by ergotherapy. With the help of special devices, adjustments,and psychological care, ergotherapy also supports the patient's reintegration into his former social environment.

Patch-clamping of primary cardiac cells with micro-openings in polyimide films

Patch-clamping is a powerful method for investigating the function and regulation of ionic channels. Currently, great efforts are being made to automate this method. As a step towards this goal, the feasibility of patch-clamping primary cells with a microscopic opening in a planar substrate was tested. Using standard microfabrication and ion beam technology, small-diameter openings (2 and 4 microm) were formed in polyimide films (thickness 6.5 microm). Single cells (sheep Purkinje heart cells, Chinese hamster ovary cells) in a suspension were positioned on top of the opening and sucked towards the opening to improve adhesion of the cell to the planar substrate, hence increasing the seal resistance. Voltage/current measurements yielded a median seal resistance of 1.3 Mohms with 4 microm openings (n=24) and 26.0 Mohms with 2 microm openings (n = 75), respectively. With 2 microm openings, successful loose-patch recordings of TTX-sensitive inward currents and action potentials in sheep Purkinje heart cells (n = 18) were made. In rare cases, gigaseals (n = 4) were also measured, and a whole-cell configuration (n = 1) could be established. It was concluded that the simple planar patch approach is suitable for automated loose-patch recordings from cells in suspension but will hardly be suitable for high-throughput whole-cell patch-clamping with high-resistance seals.

[Neuroendocrine tumors of visual system--Merkel cell carcinoma]

PURPOSE

To describe cases of Merkel cell carcinoma. Belonging to the APUD-system tumors, the highly malignant Merkel cell carcinoma affects in 10% the ocular adnexes, 50-60% of the patients develop a metastasis to the lymph nodes, and the five year survival rate is only 38%. 30% of the tumors recur after one year.

MATERIAL AND METHODS

In the last eight years the Merkel cell carcinoma was diagnosed in four patients and was treated by wide resection, radiotherapy and cytostatic drugs. Histological and immunohistological examination was performed.

RESULTS

In three cases the carcinoma was diagnosed in the upper lid and in one case in the eyebrow. Two patients could not be cured. Characteristic is clinical uniform appearance of the tumor as painless, reddish nodule with smooth surface, telangiectatic blood vessels, fast growing and fast leading to metastasis. Furthermore, the histological characteristics of the tumor were found as well as NSE, S100 proteins and neuroendocrine granula, which allow to classify to the APUD--system and to distinguish from the more benign tumors.

CONCLUSIONS

As neuroendocrine tumor the Merkel cell carcinoma represents a high malignant tumor in ophthalmology. The certain diagnosis is only made by histological and immunohistological examination. A full-thickness resection followed by radiation, should be performed as soon as possible.

[Influence of a resistance training on pulmonary function and performance measures of patients with COPD]

BACKGROUND

Training therapy with its manifold effects should be part of a modern and multi modular treatment of the COPD. Because of the specific symptoms (e. g. muscle atrophy, dyspnea, low testosterone levels) and the deconditioning of these patients, a resistance training might meet the demands of a COPD-exercise-therapy rather than an endurance training. The aim of this research project was to evaluate the efficiency of a hypertrophic maximal strength training on various COPD relevant parameters.

METHODS

28 patients with moderate to severe COPD (m12/f16) were randomized and divided in a treatment and a control group. The patients in the treatment group underwent a resistance training (hypertrophic maximal strength training) for 12 weeks, initially two times, then three times a week.

RESULTS

Considering the results of the daily Peak-Flow-Measurement, there was no significant change in both groups, but a trend towards an improvement could be found in the treatment group. There was no difference in the change of FEV 1. The performance on the ergo cycle showed a highly significant improvement (p < 0.001) in the treatment group of 18.7 % (21.9 Watt). The results of the SGRQ showed a significant improvement (p < 0.05) of the HRQL in the treatment group. A change of the HRQL in the control group was not found.

CONCLUSIONS

These data support the hypotheses that a short term high intensity strength training programme is suitable to improve performance measures of patients with moderate to severe COPD and it might also improve pulmonary function. The conclusion can be drawn, that this kind of resistance training can be prefered as COPD-specific training therapy and offers new treatment perspectives.

An example on the value of non-randomisation in clinical trials in complementary medicine

BACKGROUND

Randomised clinical trials may in principle show a small external validity. Non-randomised clinical trials therefore are sometimes regarded as an appropriate alternative when complementary and conventional treatments are compared.

OBJECTIVES

To assess the value of advanced statistical methods in the process of estimating differences between a complementary and a conventional treatment of acute sinusitis in a non-randomised clinical trial.

METHODS

Multicentre, non-randomised, controlled clinical trial comparing 2 complementary and 3 conventional ENT centres. Patients were free to choose the physician (and hence the therapy). Treatment differences were estimated by controlling for confounders in analyses of covariance or by propensity score techniques.

RESULTS

Most potential confounders (sex, age, life-style parameters) did not have significant effects on the choice of therapy. Disease severity and previous ENT surgery were the main confounding factors. At study onset they almost cause a defined separation of both treatment groups. As a result estimated treatment differences vary substantially depending on the chosen statistical model.

CONCLUSIONS

When comparing complementary and conventional treatments, non-randomised clinical trials may be misleading. Results may be strongly biased even when advanced statistical methods are used. Trials of complex statistical designs are needed to give valid results.

A non-randomised pilot study to compare complementary and conventional treatments of acute sinusitis

BACKGROUND

It is still under discussion whether antibiotics are effective in the treatment of acute sinusitis. Moreover, they are known to have considerable side-effects. In contrast, complementary approaches are reported to have little side-effects and an equivalent efficiency.

OBJECTIVES

To assess the success of conventional and complementary treatments of acute sinusitis and to estimate the patient numbers needed to confirm therapeutic equivalence. Treatment success was measured by three different scores, assessed by both patients and physicians.

METHODS

Multicentre (2 complementary and 3 conventional ENT centres), non-randomised, controlled clinical trial with 63 patients (complementary group 30, conventional group 33 patients). To control for confounders treatment differences were estimated by propensity score techniques.

TREATMENTS

The choice of medication was entirely left to the physician. We recommended to use antibiotics, secretolytics and symptomimetics in the conventional group and a combination of the herbal remedy Sinupret((R)) and the homeopathic remedy Cinnabaris 3X in the complementary group.

RESULTS

Treatment differences varied substantially depending on the outcome measure, but they were always not clinically relevant. Conventional treatment was slightly better when the outcome was assessed by the physicians (1.8 score points) but slightly worse when it was assessed by patients (0.2 score points) or in terms of the HCG-5 quality of life score (0.8 score points). p values were always > 0.3.

CONCLUSIONS

Both treatments appear to be equally effective (or ineffective). Results might be biased because both treatment groups differed substantially. Randomised trials including at least 400 patients are needed to produce valid results.

[Alignment of the sagittal profile after surgical therapy of nonspecific destructive spondylodiscitis: ventral or ventrodorsal method--a comparison of outcomes]

From 1989 to 1998, 129 patients underwent surgery for unspecific spondylodiscitis in the Department of Orthopedics of the Free University of Berlin. Fifty-six of them were followed up, and their clinical and radiological results were evaluated in this study. The surgical results of 40 patients with only ventral removal of a focus and defect coverage with an iliac crest graft were compared to those of 16 with additional dorsal bridging instrumentation by internal fixation. A mean of 2.3 vertebrae were fused in ventral spondylodesis; the mean length of dorsal instrumentation by internal fixation was 3.8 vertebrae. Patients were followed up a mean of 5.1 years after surgery. The mean age of patients was 57.1 years at the time of surgery. Patients were postoperatively mobilized a mean of 5 days after ventrodorsal fusion. A purely ventral procedure required a mean postoperative immobilization period of 3.6 weeks and brace fitting of a mean 8.2 months. There was one case of recurrent spondylodiscitis 25 months postoperatively, which made a revision of the focus necessary. The consolidation rate of the ventral spondylodesis was 84-100% in the different subgroups. A differential view of the spinal areas and ventral fusion segments was used to make a statement about the development of the sagittal spine profile. The segmental position of the spine in the sagittal plane was assessed by comparing the segmental kyphosis angles to normal values in the literature. All subgroups submitted to combined ventrodorsal fusion had a greater preoperative segmental kyphosis angle than those undergoing ventral fusion alone. In marked segmental kyphotic false positioning, the combined ventrodorsal procedure achieved good postoperative repositioning results, and an increase in segmental kyphosis was prevented. Ventral removal of a focus and bone graft spondylodesis seem to be adequate in single-level spondylodiskitis especially in the lumbar spine, but additional dorsal instrumentation should be performed in the case of long ventral fusion.

[Correction of lumbosacral kyphosis in high grade spondylolisthesis and spondyloptosis]

Spondyloptoses, but also high-grade spondylolistheses, usually only develop at the lumbosacral junction and are nearly always classed among dysplastic spondylolistheses. Kyphosis of the lumbosacral junction leads to compensation mechanisms with increased lumbar lordosis and straightening of the pelvic tilt with involvement of the hip and knee joints. Reconstructing a physiological sagittal profile by more or less complete repositioning with permanent fusion of only the lumbosacral motion segment is thus of primary importance in the surgical management of high-grade spondylolisthesis and spondyloptosis. This aim led to the following treatment modality: Dorsal repositioning following sacral dome resection with subsequent intersomatic fusion with the posterior lumbar interbody fusion (PLIF) technique. This procedure was performed in 11 patients between January 1995 and January 1998 for six grade IV spondylolistheses and five spondyloptoses. Four patients had undergone previous surgery. Measurements of the slip angle (Boxall), sagittal translation (Taillard), sacral inclination (Boxall), and sagittal rotation (Wiltse and Winter) were done in the follow-up and to check the postoperative results. Denis' pain scale was used to classify pre- and postoperative complaints as well as those of the last examination. Only one inadequate repositioning occurred in a previously operated patient who required instrumentation from L4 to S1 after a pedicle screw had been torn out at L5. In another previously operated patient, the dura was damaged intraoperatively and managed accordingly. Postoperatively, this patient developed a unilateral nerve root syndrome, which did not improve in the further course. Another patient developed decompensation of the adjacent cranial motion segment in the follow-up period. In ten cases complete or nearly complete reposition was achieved. Firm bone consolidation was seen in all patients. Complaints were markedly reduced in all patients compared to the preoperative status.

[Post-traumatic kyphosis of the truncal vertebrae]

Assessing the initial post-traumatic situation is of imminent importance in choosing the most suitable approach for primary treatment of thoracic and lumbar spine fractures. Misjudging the static situation of the injured spine is a common reason for selecting an inadequate therapeutic procedure. The consequence is a defective spinal position with the corresponding symptoms, which usually requires a complicated surgical procedure. Our experience is based on 34 patients with a post-traumatic defective position of the thoracic and lumbar spine: 12 patients underwent primary surgical and 22 primary conservative treatment. The aim of our study was to demonstrate the initial situation and primary management as well as subsequent problems and the respective surgical procedure applied in our department for correcting and stabilizing the areas involved and to present intermediate results.

[Secondary deformities after section of primary bone tumors of the spine in children and adolescents]

Primary bone tumors and tumor-like lesions of the vertebral column are rare in children. After operative tumor resection, 25 children under the age of 17 could be reviewed in a retrospective analysis. Malignant bone tumors occurred only twice in the region of the vertebral body. No deformity was registered in 9 of 16 cases after local tumor resection with and without laminectomy on one level. In contrast, after resection of one or both facets in combination with laminectomy cranial to L4 or thoracal, progressive kyphosis was found within 6-22 months postoperatively in four cases. This required a secondary fusion. After primary fusion and instrumentation, no deformity was registered. In nine cases with a location of the tumor in the vertebral body, only two patients developed a secondary instability of the spine. Both cases had no primary fusion. The other seven patients with initial fusion and instrumentation showed no deformity within 24 up to 127 months postoperatively. These results are compared with data from the current literature.

Infection of the skin caused by Corynebacterium ulcerans and mimicking classical cutaneous diphtheria

Extrapharyngeal infections caused by Corynebacterium ulcerans have rarely been reported previously, and diphtheria toxin production has usually not been addressed. This case demonstrates that strains of C. ulcerans that produce diphtheria toxin can cause infections of the skin that completely mimic typical cutaneous diphtheria, thereby potentially providing a source of bacteria capable of causing life-threatening diseases in the patient's environment. Therefore, it is recommended to screen wound swabs for coryneform bacteria, identify all isolates, carefully assess possible toxin production, and send questionable strains to a specialist or a reference laboratory.